Faceted Citrine, 8x6mm cut oval. Citrine is part of the Quartz gemstone family. Amethyst is the best known of the Quartz gemstone family; then there is Rose Quartz and Smokey Quartz. There is also clear “White” Quartz, which is what constituted the medieval soothsayer’s “Crystal Ball”, and when cut, faceted or cabochon, for use in jewellery it is also a gemstone, though one rarely used.
The above Faceted Citrine is of Brazilian origin, a natural yellow gemstone.
All the gemstones of the Quartz Crystal Family are tough. The hardness of Quartz crystal is considered the hardness benchmark of gemstones: anything tougher than Quartz is said to be especially durable, anything less so, less so.